1.1 Types of Backups

The various kinds of backup techniques are classified on a scale
ranging from hot (the most desirable) to cold (the most
disruptive). Your goal is to keep the database system, and
associated applications and web sites, operating and responsive
while the backup is in progress.

Hot backups are performed
while the database is running. This type of backup does not block
normal database operations. It captures even changes that occur
while the backup is happening. For these reasons, hot backups are
desirable when your database “grows up”: when the
data is large enough that the backup takes significant time, and
when your data is important enough to your business so that you
must capture every last change, without taking your application,
web site, or web service offline.

MySQL Enterprise Backup does a hot backup of all InnoDB tables.
MyISAM and other non-InnoDB tables are backed up last, using the
warm backup technique: the
database continues to run, but the system is in a read-only state
during that phase of the backup.

You can also perform cold
backups while the database is stopped. To avoid service
disruption, you would typically perform such a backup from a
replication slave, which can be stopped without taking down the
entire application or web site.

Points to Remember

To back up as much data as possible during the hot backup phase,
you can designate InnoDB as the default storage engine for new
tables, or convert existing tables to use the InnoDB storage
engine. (In MySQL 5.5 and higher, InnoDB is now the default
storage engine for new tables.)

During hot and warm backups, information about the structure of
the database is retrieved automatically through a database
connection. For a cold backup, you must specify file locations
through configuration files or command-line options.